//: containers/ReadOnly.java
// Using the Collections.unmodifiable methods.
package containers;

import java.util.*;
import java.util.List;

import net.mindview.util.*;

import static net.mindview.util.Print.*;

public class ReadOnly
{
    static Collection<String> data = new ArrayList<String>(Countries.names(6));
    
    public static void main(String[] args)
    {
        Collection<String> c = Collections.unmodifiableCollection(new ArrayList<String>(data));
        print(c); // Reading is OK
        // ! c.add("one"); // Can't change it
        
        List<String> a = Collections.unmodifiableList(new ArrayList<String>(data));
        ListIterator<String> lit = a.listIterator();
        print(lit.next()); // Reading is OK
        // ! lit.add("one"); // Can't change it
        
        Set<String> s = Collections.unmodifiableSet(new HashSet<String>(data));
        print(s); // Reading is OK
        // ! s.add("one"); // Can't change it
        
        // For a SortedSet:
        Set<String> ss = Collections.unmodifiableSortedSet(new TreeSet<String>(data));
        
        Map<String, String> m = Collections.unmodifiableMap(new HashMap<String, String>(Countries.capitals(6)));
        print(m); // Reading is OK
        // ! m.put("Ralph", "Howdy!");
        
        // For a SortedMap:
        Map<String, String> sm = Collections.unmodifiableSortedMap(new TreeMap<String, String>(Countries.capitals(6)));
    }
} /*
   * Output: [ALGERIA, ANGOLA, BENIN, BOTSWANA, BULGARIA, BURKINA FASO] ALGERIA [BULGARIA, BURKINA FASO, BOTSWANA,
   * BENIN, ANGOLA, ALGERIA] {BULGARIA=Sofia, BURKINA FASO=Ouagadougou, BOTSWANA=Gaberone, BENIN=Porto-Novo,
   * ANGOLA=Luanda, ALGERIA=Algiers}
   */// :~
